GB/T 18276-2017Test-bed methods and evaluating index of dynamic property for motor vehicles (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard replaces GB/T 18276-2000 "Test-bed method and evaluating index of dynamic property of motor vehicles".

As compared with GB/T 18276-2000, the main technical changes of this standard are as follows.

- This standard is only applicable to in-use commercial vehicles equipped with ignition or compression ignition engines. Other vehicles may refer to this standard (see clause 1).

- DELETE the terms and definitions of net power, measured driving wheel power, corrected driving wheel power and simulated inertia, ADD the terms and definitions of "driving wheel power" (see clause 3; clause 2 of 2000 version);

- DELETE the "test conditions" (see clause 3.3 of the 2000 version);

- ADD the "test equipment" requirements (see clause 6);

- ADD the "test preparation" requirements (see clause 6);

- MODIFY the "detection method", PROVIDE specific detection method based on different detection working conditions, DELETE the acceleration time, coast-down distance, and time test (see clause 8; clause 4 of 2000 version);

- ADD the "evaluation of test results" (see clause 9);

- MODIFY the "limit" (see 9.1; clause 3.4 of 2000 version);

- DELETE the "Basic requirements for dual drum chassis dynamometers", "Automotive dynamic performance test form", and "Calculated radius of automobile tires" (see Appendix A, Appendix B, Appendix D of the 2000 version);

- ADD the "Recommended vehicle speed and driving wheel power at maximum torque condition" (see Appendix A);

- MODIFY the "Correction method of driving wheel power" (see Appendix B; Appendix C of the 2000 version).

1 Scope

This standard specifies the test bed test parameters, evaluation indicators, testing equipment, testing preparations, testing methods, and testing results assessment, etc., of the dynamic properties of motor vehicles.

This standard applies to the in-service commercial vehicles equipped with ignition or compression ignition engines, other vehicles may refer to this standard.

2 Normative references

The following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) are applicable to this standard.

GB/T 2977 Size designation, dimensions, inflation pressure and load capacity for truck tires

3 Terms and definitions

The following terms and definitions apply to this document.

6 Testing equipment

6.1 The dynamometer shall meet the technical requirements of JT/T 445.

6.2 Double drive-axle vehicle testing shall use a three-axle six-roller dynamometer.

6.3 It is equipped with ambient temperature, relative humidity, atmospheric pressure measurement device, temperature measurement device measurement accuracy is ± 1.5 K, relative humidity measurement device measurement accuracy is ± 5%, atmospheric pressure measurement device measurement accuracy is ± 0.5 kPa.

7 Testing preparation

8 Testing methods

8.1.1.2 The pilot drives the vehicle steadily up to the dynamometer and sets the driving wheel of the vehicle on the drum. The axis of the driving wheel shall be parallel with the axis of the drum, fix the non-driving wheel of the vehicle.

8.1.1.3 Start the motor vehicle, gradually accelerate, move the transmission to the direct gear (the automatic transmission shall be placed in "D" position), so that the motor vehicle can run stably with the minimum speed of the direct gear.

8.1.1.4 Set the speed of the vehicle in accordance with the maximum torque condition as determined in 8.1.1.1, the dynamometer performs constant speed power metering.

8.1.1.5 Load the dynamometer, step the acceleration pedal to the end, after the vehicle speed is stabilized for 5 s at set speed, read the average value of the measured power of the dynamometer for not less than 3 s, take record.

8.1.1.6 During the reading, the actual speed shall be stabilized within the set speed ± 0.5 km/h.

Appendix B (Normative) Driving wheel power correction method